| 摘要 |
The present invention relates to a method of improving data obtained by radar by interpolation over frequency bands jammed by narrow-band interference, at which the following steps (A)-(J) are carried out. (A) it is determined what frequency values are affected by narrow-band interference. (B) Every radar return which is continuously connected in time and represented by a time-discrete real or complex signal f(t i), containing N sample, i=1,2,...,N, is Fourier-transformed into a frequency-discrete function F(.omega.i), given by N sample. (C) A series of integers N1, N2,...,N M is fixed, such that 1.ltoreq.N1<N2<...<N M<N. (D) The signal processing device sets F k(.omega.i)=F(.omega.i) outside narrow-band interference and F k(.omega.i)=H k(.omega.i) within intervals having narrow-band interference. (E) H1(.omega.i) is equated to 0 and H k(.omega.i) for k.gtoreq.2 is constructed according to the following steps (F)-(H). (F) F k-1(.omega.i) is inversely Fourier-transformed into a time-discrete function f k-1(t i). (G) The signal processing device sets h k(t i)=f k-1(t i) for i=1,2,...,N k-1, wherein ¦f k-1(t i)¦ constitute the N k-1 greatest values of ¦f k-1(t i)¦ and h k(t i)=0 for the remaining N-N k-1 values of the function. (H) h k(t i) is Fourier-transformed into a frequency-discretef unction H k(.omega.i). (I) Steps (D)-(H) are repeated M times, wherein 1.ltoreq.k.ltoreq.M. (J) F NM(.omega.i) is inversely Fourier-transformed to give the finally filtered radar return f NM(t i).
|
